NHS Grampian faces "significant pressures" and will not achieve financial balance without a major redesign of its health and social care system, auditors warn.
According to the report, the health board's current cost base is “unsustainable for future operations based on current funding levels” and warned that fundamental changes to the way services are designed and funded will be required.
NHS Grampian was escalated to stage four of the NHS Scotland Support and Intervention Framework earlier this year due to concerns about its financial stability, leadership and governance.
The Audit Scotland report urged the board to agree a financial recover plan “as soon as possible” and outline how it intends to return to balance.
Earlier this year, NHS Grampian received a £67million loan from the Scottish Government to help tackle its overspend.
The new report said: "The move to stage four highlights the significant financial pressures on the board and the significant challenge it will face to bridge the financial gap over the medium term.
"NHS Grampian should agree a financial recovery plan as soon as possible and clearly set out how the board intends to return to financial balance."
Recently-appointed chief executive Laura Skaife-Knight said the audit was a “constructive way to reflect on our challenges."
She added: "We're developing an improvement plan in close collaboration with our staff and partners, building on work already under way, recognising this is how we will meet the challenges we face and that lie ahead.
"This improvement plan will come to our public board meeting in December 2025 for approval, for transparency, and regular progress updates will be shared with our community, partners and staff."
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